Torrential downpours that have battered New Zealand for four days straight have caused floods that could take years to clean up and displaced at least 1,200 people from their homes in the top of the South Island.
Friday’s rain comes on top of weeks of wet weather and is worsening conditions in New Zealand’s already sodden landscape. Experts have attributed the unseasonably wet weather to a narrow stream of water vapour, or “atmospheric river”, sitting above the country.
Evacuated residents in Nelson, a city with a population of more than 50,000 that has been particularly hard hit, were told they were unlikely to be able to return home on Friday, leaving 1,200 people from 411 households displaced. Nelson’s mayor, Rachel Reese, told media it would take years to recover from the flooding, which has badly damaged roads and homes.
Local Civil Defence group controller Alec Louverdis struggled to hide his emotion over the damage he had witnessed, including extensive slips. “The damage that I saw in Nelson was heartbreaking,” he said. “We are years away from a recovery.”
Some residents are being warned they may not be able to return to their homes, which will be damaged beyond repair. Communities in other areas, including the north-western tip of the Marlborough Sounds, had been cut off and were running low on supplies.
The bad weather shows little sign of letting up and the threat of landslides is hampering efforts to safely return people to their homes. Most evacuees had gone to stay with family and friends, Louverdis said.
Another 130mm of rain is expected in the region on Friday night, on top of at least 172mm that has fallen since Tuesday in Nelson – well above its average rainfall for the whole of August of 80mm.
Paradise Peak in the Tasman recorded an extraordinary 795mm of rain from midday Tuesday to 9am Friday, while Dawson Falls in Taranaki region recorded just over a metre, according to Metservice.
Some Taranaki residents had voluntarily evacuated their homes due to high river flows.
The Civil Defence is monitoring river levels, but is hopeful it will not have to close the Waitara town bridge that crosses into Waitara town. Schools had sent their children home fearing a bridge closure could leave families split up on opposite sides of the river, RNZ reported.
The top of the North Island is also bearing the brunt of the deluge, with multiple roads and state highways closed due to slips, fallen trees and flooding. Some residents have also evacuated their homes in the small town of Kaitāia.
More than 40 locations have had record, or near-record rainfall totals this winter, said Dr Daniel Kingston, a senior geography lecturer at the University of Otago.
“That is linked to a higher than usual number of atmospheric rivers occurring. Normally, atmospheric rivers are relatively rare during the winter months.”
Climate change is likely playing a role, and warming air and sea surface temperatures are likely playing a role he said.
“As the atmosphere warms it can hold more moisture, increasing the likelihood for extreme heavy rainfall events such as this.”